Circular knitting machine with multiple knitting systems

ABSTRACT

A circular knitting machine in which a large number of knitting systems are circumferentially distributed about the common axis of the needle cylinder and cam cylinder. The needle cylinder carries next to the needles, needle jacks which are tilted between operative and inoperative positions by pattern jacks. A selecting structure is provided for controlling the pattern jacks so as to actuate the latter to tilt the needle jacks between their operative and inoperative positions, and those needle jacks which are in an inoperative position are automatically displaced to an operative position prior to each selection in a collecting region in axial alignment with a given knitting system, the actual selection for one knitting system being made in the space occupied by the immediately preceding knitting system, so that in this way it is possible to situate in cylinders of a given diameter an extremely large number of knitting systems.

O United States Patent 1 1 3,802,224

Plath 1451 Apr. 9, 1974 [54] CIRCULAR KNITTING MACHINE WITH 3,641,787 2/1972 Robottom 66/50 R MULTIPLE KNITTING SYSTEMS FOREIGN PATENTS OR APPLICATIONS 1 1 lnvemerl Ernst-Dieter Plath, Tailfingen, 996,291 6/1965 Great Britain 66/50 B Germany 705,358 5/1966 ltaly 66/50 R [73] Assignee: Mayer & Cie, Tailfingen Wurtt.,

Germany Primary Examiner-Wm. Carter Reynolds [22] Filed: June 3, 1971 N 149 479 [57] ABSTRACT [21] Appl' o'- A circular knitting machine in which a large number of knitting systems are circumferentially distributed [30] Foreign Applicafilm Priority Data about the common axis of the needle cylinder and June 9, 1970 Germany 2028188 cam cylinder. The needle cylinder carries next to the needles, needle jacks which are tilted between opera- [52] US. Cl 66/50 R tive and inoperative positions by pattern jacks. A se- [51] Int. Cl D04b 15/68 lecting structure is provided for controlling the pattern Field of Search /50 R, 50 B, 25, 36 A, jacks so as to actuate the latter to tilt the needle jacks 66/36 B, 42 between their operative and inoperative positions, and those needle jacks which are in an inoperative position [56] References Cited are automatically displaced to an operative position UNITED STATES PATENTS prior to each selection in a collecting region in axial 1,873,502 8/1932 Steinmuller 66/36 A aligflmem with a f knitting System; the acnfal 3'063269 11/1962 Losenetalw 66/5ORX lection for one knIttIng system beIng made In the 3,283,540 11/1966 Levin 66/36 A Spaee Oeeupied y the immediately Preceding knitting 3,499,300 3/1970 Zahradkam. 66/50 R X system, so that in this way it is possible to situate in 3,577,749 5/1971 Wright 1 I 616/50 R cylinders of a given diameter an extremely large num- 3,616,654 1 H1971 Llinas 66/25 ber of knitting systems 3,623,341 11/1971 Fetzer I 66/42 I 3,638,456 2/1972 Guell 66/50 R 5 Claims, 6 Drawing Figures f 16A 1581 183 1 22B 1 l I y 11 22A 1:1f1 10:1:1111'11114 2e 1 11 1 Ii ii 111 B A 271 I l 12A 1: ==l =2 E g ==l |==I 2: a;

i 1 I==I I I 1= z: I? :T

."ATENTEUAPR 9 I974 SHEET 3 OF 3 INVENTOR ERNST-DI ETER PLATH vmncsw ATTORNEY CIRCULAR KNITTING MACHINE WITH MULTIPLE KNITTING SYSTEMS BACKGROUND OF THE INVENTION The present invention relates to circular knitting machines.

Thus, the present invention relates to multiplesystem circular knitting machines provided with a Jacquard type of pattern selection device where for each knitting system there is a pattern selecting pin drum which through swingable selecting members during the rotation of the needle cylinder brings about tilting of pattern jacks which coact with tiltable needle jacks for tilting the latter between operative and inoperative positions. In this way it is possible to control the needle jacks by way of needle jack cams and the needles by way of needle cams all of which are carried by the cam cylinder.

It is already been proposed, in order to reduce the circumferential length of each individual knitting system of a circular knitting machine, so as to increase the number of knitting systems distributed circumferentially about the machine, to eliminate distinct yarntaking regions and to shorten the length of the loopsinking eccentric. An additional shortening of the circumferential length of each knitting system is achieved by providing a sharp angle of slope for the cam edge which raises a needle to a yarn-taking position, as well as a corresponding sharp slope for the needle butt when it is pulled back down to the loop-sinking position, but these sharp cam slopes can only be provided at the cost of reducing the speed of rotation of the machine because otherwise there will be an undesirable large frequency of breakages of the needle butts. Because of the reduced speed of rotation of the machine which is necessitated by such circumferentially compressed knitting systems, the advantage ofa large number of knitting systems circumferentially distributed about the machine is largely negated. The elimination of precisely determined yarn-taking regions in the cam system with the known machines does not in any way limit the knitting systems only to the actual operating regions of the needles where they are raised to the yarn-taking locations and pulled down to the loopsinking positions, since it is also essential to include in these circumferential knitting systems a starting region where all of the needles or the control elements which coact therewith must be collected in preparation for a selection so that suitable pattern selections can be made. A further reduction in the circumferential length of the individual knitting systems thus can only be achieved by shortening or eliminating the control region for the individual knitting systems.

SUMMARY OF THE INVENTION It is accordingly a primary object of the present invention to provide a circular knitting machine with a Jacquard type of pattern selection arrangement which can accommodate a substantially larger number of knitting systems than was heretofore possible, with full possibility of pattern selection and where although there are a large number of knitting systems nevertheless the patterns which are selected need not have any slope and can extend through a large area of the knitted goods before being repeated.

A further object of the present invention is to provide a circular knitting machine in which those needle jacks which are in their operative positions remain in the latter positions to return to a collecting station prior to each selection while those needle jacks which are in inoperative positions are automatically returned to their operative positions when arriving at the collecting station just prior to the next selection.

A further object of the present invention is to provide a selecting arrangement which enables the selections for one knitting system to be carried out in such a way that at least the collection of the needle jacks and pattern jacks at the collecting station just prior to a given selection takes place at a knitting system which immediately precedes the knitting system where the actual knitting takes place according to the selection which is made.

Also, it is an object of the present invention to provide a construction of this type which is characterized by great simplicity and reliability in operation.

Thus, it is an object of the present invention to limit the circumferential length of each knitting system to the angular distance required only for raising a needle to the yarn-taking position and lowering it to the loopsinking position, with the pattern-selecting structure overlapping the knitting system which immediately precedes the system where the knitting takes place.

In accordance with the invention each needle jack is provided with three butts, namely a raising butt, a pulldown butt, and a tilting butt, and the needle jack cams provide three distinct cam paths for these three butts of each needle jack. The coaction between the tilting butt and raising butt of each needle jack is controlled by way of the pattern jack. The cam path for the tilting butts of the needle jacks extends circumferentially around the common axis of the cylinders in a plane normal thereto, and at each knitting system there is in this latter cam path a spring-pressed return cam which engages the tilting butt of each needle jack which is in an inoperative position for tilting the latter back to an operative position at the collecting station just prior to a selection which is made for the next-following knitting system. The needle jack cams include raising cams for coacting with the raising butts to raise the needle jacks, and each raising cam is formed in axial alignment with each return cam with an elongated cutout for receiving the raising butt of a needle jack which is tilted back to its operative position by a return cam.

BRIEF DESCRIPTION OF DRAWINGS The invention is illustrated by way of example in the accompanying drawings which form part of this application and in which:

FIG. 1 is a highly schematic fragmentary developed view of a cam cylinder where some of the knitting systems are illustrated; and

FIGS. 2-6 are respectively schematic fragmentary longitudinal sectional elevations taken along line II-II to VI-VI of FIG. 1 in the direction of the arrows.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring to the highly schematic fragmentary illustration of the cam cylinder in FIG. 1, it will be seen that the cam cylinder 23 carries a needle cam means 10 and a needle jack cam means 11. These cam means are circumferentially distributed about the common axis of the cam cylinder 23 and needle cylinder 25 so as to form the several knitting systems A, B, C, D, etc. The I several components of the various knitting systems are designated by the same reference characters followed by the letters which indicate the different knitting systems. Each knitting system is provided with a selecting means located at a selecting station, and for this purpose there is for each knittingsystem a pattern selecting pin roller which in a known way actuates swingable pattern-selecting members 12 of each system, these selecting members 12 forming a selecting means. It will be noted that, for example, the selecting means 128 for the system B overlaps in part the immediately preceding knitting system A, the selecting means 12C for the knitting system C overlaps in part the immediately preceding system B, and so on.

In the description which follows, details of the knitting system A will be described, but it is to be understood that the same details are included in the remaining knitting systems only four of which are illustrated.

Thus, the needles 13 are respectively provided with needle butts 131, and the system A includes a cam 14A co-acting with the butt 131 of each needle 13 during raising of the latter to the yarn-taking position aswell as a loop-sinking cam 15A for coacting with the butt 131 of each needle 13 for returning the latter down to the loop-sinking position. These knitting operations take place during operation of the circular knitting machine, and' it will be noted that while an operating needle will be controlled by the cams 14A and 15A, as indicated in FIG. I, a non-operating needle will have its butt 131 simply rotating circumferentially about the axis without moving axially, as indicated for the path of the butt 131 schematically shown at the knitting system B. For this purpose the needle butts are guided by the top edges of the cams 16A, 163, etc. Thus all of these cams referred to above form a needle-cam means for controlling the needles. This needle cam means includes an additional cam 17A situated in axial alignment with the loop-sinking cam 15A.

The cam cylinder 23 also carries a needle jack cam means 11 which provides three cam paths for the three butts of each needle jack 18. Thus, each needle jack 18 has a pull-down butt 182, a tilting butt 183, and a raising butt 181. In order to control the raising'butts 181 of the needle jacks, the cam means 11 includes at each knitting system a raising cam 19A, 198, etc. The cam 19A is formed with an elongated circumferentially extending cutout 20A. The guiding of the pull-down butt 182 is brought about by a cam 21A and a cam path 28 extends circumferentially about the common axis of the needle and cam cylinders in. a plane normal thereto and serves to form a cam path for the tilting butts 183 of the needle jacks. This cam path 28 is defined on one side by the cam 16A and on the other side by the cam 21A. At each of the knitting systems there is at the cam path 28 a spring-pressed return cam 22A, 2213, etc., which coacts with the tilting butt 183 in a manner described in greater detail below.

As is apparent from FIG. 1, the needle cam means and the needle jack cam means are all made up of identical components at the several knitting systems.

The construction of each needle jack with its three butts 181-183 is apparent from FIG. 2 which illustrates the cam cylinder 23 at the region of the system A as well as the needle cylinder 24 with its lower cylinder portion 25 and the cylinder carrier ring 26. The needles 13 together with the needle jacks 18 and the pattern jacks 27 are situated in a known way'in vertically extending grooves 252 which are formed on the needle cylinder 24 as well as its lower portion 25. The needle jacks 18 are each formed at an edge opposed to the jack butts with a tilting point 184 situated between the pull-down butt 182 and the raising butt 181, and the several jacks and needles are situated with a light friction in the several grooves 252.

Each needle jack 18 coacts with a pattern jack 27 which has an upper head end 271 overlapping the front edge at the lower end region of each needle jack 18. Each pattern jack 27 has a lower substantially circular end 272 engaging a flange 251 of the lower cylinder portion 25 so as to rest on this flange. At its intermediate region each pattern jack has a pattern butt 273 which at the selecting station can be engaged by a swingable selecting rod of a selecting means such as the selecting means 12A. As is apparent from FIG. 1 the several pattern butts 273 of adjoining pattern jacks 27 are axially displaced so that the several pattern butts of a series of pattern jacks 27 are arranged along a spiral in the manner indicated schematically in FIG. 1 at the lower needle cylinder portion 25.

The operation of the above described structure is set forth below in connection with FIGS. 2-6.

The section of FIG. 2 is-taken at the system A at the starting region thereof close to the location of the selecting station for this particular system A. It is assumed that at the immediately preceding knitting system the pattern butts 273 of the pattern jacks 27 have not been displaced by the selecting means 12A, so that the result is that the several needle jacks 18 which coact with the pattern jacks remain in their operative positions where the raising butts 181 are in the range of action of the raising cam 19A. Thus, during rotation of the needle cylinder with respect to the stationary cam cylinder the raising butts 181 of the needle jacks 18 will engage the upper edge of the cam 19A to be raised thereby, so that the needle jacks are raised and at their upper ends engage the lower ends of the needles 13.

In this way the needles 13 are raised while their butts 131 move along the cam 14A to be guided thereby, in

' order to rise up to the yarn-taking position, whereupon the needles are returned back down to their starting positions by the loop-sinking cam 15A. During this operation of the needle jacks 18 and needles 13, the tilting butt 183 of each needle jack moves along the outer surface of the cam 16A, which is to say the surface thereof which is directed toward the needle cylinder 24, so that it is not possible for the needle jack 18 to be tilted at this time inasmuch as such tilting is blocked by the right surface of the cam 16A, as viewed in FIG. 2, engaging the tilting butt 183 when the latter moves along the path indicated schematically at the knitting system A in FIG. 1. The return of the needle jack 18 to the position shown in FIG. 2 takes place by way of the pull-down butt 182 which engages the lower camming edge of the cam 21A, forming a pull-down cam for the needle jack cam means of the system A.

FIG. 3 illustrates the situation where the selecting means 128 has been operated to act on the pattern butts 273 of the pattern jacks 27 for preventing operation of needles at the system B. The displacement of the selecting means 12B to a position for coacting with the pattern butts 273 results in tilting of the pattern jacks 27 in a clockwise direction from the position of FIG. 2 into the position of FIG. 3, about their circular bottom ends 272, into the corresponding vertical grooves 252. As a result the upper head end 271 of each pattern jack 27 engages the coacting needle jack 18 at its lower end and brings about a tilting of this needle jack 18 about its tilting point 184 in a counterclockwise direction from the position of FIG. 2 into the position of FIG. 3. As a result the raising butt 181 of the needle jack 18 is displaced beyond the raising cam 19B and the tilting butt 183 of the needle jack 18 is tilted into the cam path 28 at the knitting system B. As a result these needle jacks 18 are not raised, and the raising butts 181 thereof move along the exterior right surface of the cam 19B, as viewed in FIG. 3, this being the surface of the cam 198 which is directed toward the jack 18. Thus, the needles 13 above these needle jacks which are in their inoperative positions are not raised and the needle butts 131 therefore move circumferentially around the common axis of the needle cam cylinders without moving axially with respect thereto, as indicated at the system B in FIG. 1.

When each jack 18 has moved approximately half way through the system B, the tilting butt 183 thereof engages the return cam 22B. This cam 228 will now engage the tilting butt 183 of each jack 18 to tilt the latter back to the operating position, as illustrated in FIG. 4. Thus, FIG. 4 illustrated in section the return cam 22B and the spring 221 which urges it to the right, as viewed in FIG. 4. When each needle jack 18 is tilted back to its operating position by the return cam 22B, its raising butt 181 enters into the cutout B of the raising cam 198, so that the return tilting of each needle jack 18 to its operative position is not in any way hindered by the raising cam 19B.

During the continued rotary movement of the needle cylinder, each pattern jack 27 will reach the selecting station for the next-following system C. Of course, the return of each needle jack 18 to its operative position by the return cam 228 has placed the pattern butt 273 into the operating range of the selecting means 12C. As is illustrated in FIG. 5, at this location the pattern jacks 27 are not influenced by the selecting elements of the selecting means 12C. Therefore the pattern jacks remain in the positions shown in FIG. 5, and the needle jacks 18 remain in their operating positions, so that the raising butts 181 thereof will be acted upon by the raising cam 19C which raises the needles jacks 18 which thus raise the needles 13 to the position indicated in FIG. 6. This is the position where each needle will take yarn before being pulled-down to the loop-sinking position. As is apparent from FIG. 6, during the knitting operation it is not possible for a pattern jack 27 to provide tilting of a needle jack 18 because the tilting butt 183 engages the exterior surface of the cam 16C and is not in alignment with the cam path 28. As a result, the return cam 22C will also have no influence on the needle jack 18.

As indicated in the fragmentary developed illustration of FIG. 1, the circumferential length of each knitting system has a magnitude a which is precisely equal to the circumferential length of each knitting system. The selecting region required for pattern selection of the needle jacks for each knitting system includes the collecting station I) where all of the previously selected needle jacks 18 are returned by the cam 22 into their operating positions. This collecting region b is defined between the circumferential distances 0 required by a pair of successive selecting means such as the selecting means 12C and 12D shown in FIG. 1. Thus a selection region is made up first of the preliminary collecting region b and then the region c where actual selection is made.

It will be noted that the collecting region or station b for each knitting system is entirely located in circumferential alignment with the immediately preceding knitting system. The selecting region c where the selection actually takes place also overlaps to a large extent the immediately preceding knitting system. As a result of this extending of the selecting operations into the region of a knitting system which immediately precedes the system where operations are made in accordance with the particular selection, it is possible to very greatly reduce the circumferential distance required by the several knitting systems.

It is to be noted that the return of a previously selected needle jack which has been displaced to its inoperative position, into its operative position takes place simultaneously with the operation of a needle coacting with a jack which is raised by a raising cam and which has not been selected. Such a non-selected jack will also return while remaining in its operating position during the loop-sinking of the needle with which it cooperates, so that in this way an operating needle jack will also be situated at the collecting region in preparation for the next selection together with jacks which have been tilted back to their operating positions. It is thus possible to provide for each knitting system of the machine of the invention an operating region whose circumferential length is equal only to that required for displacing a needle out of a yarn-taking position and returning it to the loop-sinking position. The collection of the various nee dle jacks in preparation for a new selection takes place at a system which immediately precedes the system where the operations are made in accordance with the selections. Thus, non-selected jacks will provide for operation ofthe needles in a given knitting system while the selected jacks will prevent selected needles from operating.

With the above-described structure of the invention and in particular with the above construction of the needle jacks, the number of knitting systems which can be distributed about the common axis of the needle and cam cylinders of a given machine can be very sharply increased. For example, where a machine normally would have 39 knitting systems it is possible with the present invention to provide it with 64 knitting systems.

Any costs or other disadvantages which might result from the structure of the cams and needle controlling elements of the invention is more than compensated for by the enlarged pattern possibilities and by the magnitude of a given pattern before repetition thereof is required. If for comparison the use of pattern wheels in the operating range of the needles is considered, then the size of the repeating pattern will be very sharply limited and there will be practically no possibility of achieving non-sloping patterns, so that it becomes extremely difficult for a designer to adjust the pattern structure for machines of this type. With a circular knitting machine according to the present invention, however, which is built for use with Jacquard devices having pin drums, it is possible with a two-color pattern, for example, to achieve patterns which may extend through a range on the order of 60 wales and 384 courses, before pattern repetition is required, and in the case of symmetrical patterns the width of each patten, before it is repeated, can be extended over 120 wales.

Although the invention is illustrated and described with reference to one preferred embodiment thereof, it is to be expressly understood that it is in no way limited to the disclosure of such a preferred embodiment, but is capable of numerous modifications within the scope of the appended claims.

What is claimed is:

1. In a circular knitting machine, coaxial needle and cam cylinders one of which rotates with respect to the other, said needle cylinder being formed with a series of axial grooves in each of which said needle cylinder carries an elongated needle, an elongated needle jack next to said needle tiltably and longitudinally slidably disposed in each groove, and an elongated and only tiltably movable pattern jack in each groove next to and coactin g with said needle jack for tilting the latter between operative and inoperative positions, said cam cylinder being circumferentially divided into a series of knitting systems each of which includes in alignment radially of said cylinders with said needles a needle cam means on the cam cylinder having a circumferential length including substantially only a surface for lowering the needles which have been raised back down to a loop-sinking position, and said cam cylinder carrying a needle jack cam means at each knitting system aligned radially'of said cylinders with said needle jacks for coacting therewith when said jacks are in their operative positions for raising the needles to the yarn taking position and for remaining out of operative coaction with said needle jacks when the latter are in their inoperative positions, said knitting systems being circumferentially distributed one directly next to the other without any interruption around the common axis of said cylinders, and a plurality of selecting means circumferentially distributed about the common axis of said cylinders in alignment radially of said cylinders with said pattern jacks for tilting the latter or for not tilting the latter according to given selections, said needle cam means, needle jack cam means and selecting means having defined operative ranges corresponding in number to the number of knitting systems, the operative range of each selecting means overlapping at least partially with the operative range of the next preceding needle and needle jack cam means, said plurality of selecting means equaling the number of knitting systems, and wherein each needle jack has a raising butt, a pulldown butt, and a tilting butt, said needle jack cam means providing three cam paths for said butts of each needle jack, respectively, and said pattern jacks respectively tilting said needle jacks to control the coaction of said tilting and raising butts thereof with their coacting paths.

2. The combination of claim 1 and wherein said needle jack cam means includes at each knitting system a needle jack raising cam for coacting with the raising butt of each needle jack to raise each needle jack which is in an operative position, and each raising cam being formed in axial alignment with the collecting station for the next-following knitting system, with an elongated cutout for receiving the raising butt of each needle jack which is tilted from its inoperative to its operative position at the collecting station.

3. The combination of claim 2 and wherein the needle jack cam means of each knitting system includes in the cam path of each tilting butt a return cam and a spring urging the return cam toward the tilting butt, said return cam being vertically aligned with said cutout of said raising cam of the corresponding system and engaging the tilting butt of each needle jack which is in an inoperative position for tilting the jack back to an operative position while the raising butt thereof enters into said cutout.

4. The combination of claim 1 and wherein each needle jack has its raising butt and tilting butt respectively situated at opposed end regions of each needle jack and each pattern jack coacting with each needle jack at that end region thereof where said raising butt is located, and each needle jack having at an edge opposed to that where said butts thereof are located a tilting point situated between the pull-down butt and the raising butt of each needle jack.

5. The combination of claim 1, and wherein the operative ranges of said selecting means are circumferentially spaced from each other for forming selecting stations and defining between the selecting stations collecting stations in which the pattern jacks are situated preliminary to selections, the collecting of all needle jacks in. the operative range of each needle jack cam means for one knitting system being carried out completely in the region of the operative range of the corresponding needle jack cam means. 

1. In a circular knitting machine, coaxial needle and cam cylinders one of which rotates with respect to the other, said needle cylinder being formed with a series of axial grooves in each of which said needle cylinder carries an elongated needle, an elongated needle jack next to said needle tiltably and longitudinally slidably disposed in each groove, and an elongated and only tiltably movable pattern jack in each groove next to and coacting with said needle jack for tilting the latter between operative and inoperative positions, said cam cylinder being circumferentially divided into a series of knitting systems each of which includes in alignment radially of said cylinders with said needles a needle cam means on the cam cylinder having a circumferential length including substantially only a surface for lowering the needles which have been raised back down To a loopsinking position, and said cam cylinder carrying a needle jack cam means at each knitting system aligned radially of said cylinders with said needle jacks for coacting therewith when said jacks are in their operative positions for raising the needles to the yarn taking position and for remaining out of operative coaction with said needle jacks when the latter are in their inoperative positions, said knitting systems being circumferentially distributed one directly next to the other without any interruption around the common axis of said cylinders, and a plurality of selecting means circumferentially distributed about the common axis of said cylinders in alignment radially of said cylinders with said pattern jacks for tilting the latter or for not tilting the latter according to given selections, said needle cam means, needle jack cam means and selecting means having defined operative ranges corresponding in number to the number of knitting systems, the operative range of each selecting means overlapping at least partially with the operative range of the next preceding needle and needle jack cam means, said plurality of selecting means equaling the number of knitting systems, and wherein each needle jack has a raising butt, a pull-down butt, and a tilting butt, said needle jack cam means providing three cam paths for said butts of each needle jack, respectively, and said pattern jacks respectively tilting said needle jacks to control the coaction of said tilting and raising butts thereof with their coacting paths.
 2. The combination of claim 1 and wherein said needle jack cam means includes at each knitting system a needle jack raising cam for coacting with the raising butt of each needle jack to raise each needle jack which is in an operative position, and each raising cam being formed in axial alignment with the collecting station for the next-following knitting system, with an elongated cutout for receiving the raising butt of each needle jack which is tilted from its inoperative to its operative position at the collecting station.
 3. The combination of claim 2 and wherein the needle jack cam means of each knitting system includes in the cam path of each tilting butt a return cam and a spring urging the return cam toward the tilting butt, said return cam being vertically aligned with said cutout of said raising cam of the corresponding system and engaging the tilting butt of each needle jack which is in an inoperative position for tilting the jack back to an operative position while the raising butt thereof enters into said cutout.
 4. The combination of claim 1 and wherein each needle jack has its raising butt and tilting butt respectively situated at opposed end regions of each needle jack and each pattern jack coacting with each needle jack at that end region thereof where said raising butt is located, and each needle jack having at an edge opposed to that where said butts thereof are located a tilting point situated between the pull-down butt and the raising butt of each needle jack.
 5. The combination of claim 1, and wherein the operative ranges of said selecting means are circumferentially spaced from each other for forming selecting stations and defining between the selecting stations collecting stations in which the pattern jacks are situated preliminary to selections, the collecting of all needle jacks in the operative range of each needle jack cam means for one knitting system being carried out completely in the region of the operative range of the corresponding needle jack cam means. 